Skip to Main Content

Literature Reviews - Research Guide

Searching for Literature

Searching for Literature

To ensure the quality and relevance of literature* that you include in your literature review, remember:

  •  The age of material is important - you should start with the most recent sources and work backwards
  •  It is important to use a variety of resources - the literature may include books, book chapters, journal articles, conference papers, theses, statistics, empirical data, government publications and research reports
  •  You may need to search for authors, as well as keywords and subjects
  •  You will need to review and evaluate your search results, and modify your search strategy if necessary
  •  It is critical to develop good referencing skills (see Managing your Results)
  • You can broaden your search by looking  for literature in related disciplines, by using the reference lists of any relevant sources you have already identified, or by using citation databases

Where to search

When searching for literature, you can use Library Search to identify and locate books, reports, conference proceedings, theses and other resources.

You can determine relevant databases to search for journal articles and conference papers using the By subject menu on our Databases page or the list of key databases in the relevant Subject Guide.

Some important databases for literature reviews include:

Your supervisor may suggest relevant resources and databases.

Please note that you can contact our Librarians who can assist you with refining your search strategy, identify relevant databases and resources, demonstrate database features and functionality, and demonstrate methods for obtaining more obscure resources.

Using a search diary

During your literature review you will carry out a number of searches and gather many references -  it is easy to lose track of a particular reference, which databases you have searched, which keywords you used, or how you identified a source.  It is helpful to keep a search diary, in whatever format you prefer, to record:

  •     When you searched
  •     Where you searched (name of database, or catalogue) 
  •     Search terms and combinations of terms that were successful
  •     Search terms and combinations of terms that were not successful
  •     Searches or leads you want to follow in the future
* Literature

'Literature' can include a range of sources:​ ​

  • Journal articles
    • Primary method of academic and scientific publishing​ ​
    • Provide supporting evidence for current and future research​ ​
    • Provide a wide range and large volume of research publications​ ​
    • Allow research to be published rapidly​ ​
    • Provide very specific research data​ ​
    • Undergo a quality peer review process prior to publication
  • Books and book chapters​
  • Statistical or factual databases​
  • Conference proceedings​
  • Theses​
  • Empirical or observational studies​
  • Reports from government agencies and other research organisations​
  • Archival material

Developing a Search Strategy

Once you have formulated your review topic, you can devise your search strategy:

Keyword and phrase search

Use the main concepts and keywords of the review topic as the basis of your search strategy.
When searching for phrases, place your search terms in double inverted commas - for example, "public health".
This will search for the words as a phrase and in that order. 
Tip: Turn off smart quotes (curly quotation marks) in your Word document, as the formatting corrupts search strings - for example "public health" rather than public health

When creating a search strategy, consider synonyms for your keywords and group them together as a concept string.
Identify subject-specific terms for your topic in textbooks, lecture notes, subject-specific encyclopaedias and dictionaries or articles.
Tip: alphabetise search words to easily identify duplication

Check that each search word adds value to your search  i.e. that it returns relevant results.

In some disciplines, you may need to combine keywords and phrases with controlled vocabulary terms  (eg Medical Subject Headings) to comprehensively describe your review topic.
Example ("hand disinfection" OR "hand hygiene" OR handwash*)

Search the main concepts first, then limit further as necessary.

Be aware of differences in American and English spelling and terminology.
Most databases use American spelling and terminology as preferred subject terms.

Include hyphenated words a both one word, as well as a phrase.
Do not include punctuation (databases either ignore a hyphen, or it corrupts the search string).
For example (noncoding OR "non coding").

Include abbreviations.
For example: ("superior thalamic radiation" OR STR)

Search types

The blog post Structure of search strategies for systematic reviews: Line by line versus block by block versus single-line explains the different ways of structuring a search.

Use connectors (Boolean operators)

Boolean operators connect phrases or keywords to improve your search results.
These determine the relationship between concepts:

Operator Action Example


broadens your search showing results with at least one of your keywords paediatric OR child*
AND narrows your search showing results which contain both keywords stress AND workplace
NOT narrows your search excluding certain words from your results rabies NOT dog

Use truncation/stemming and wildcard symbols

A truncator is used to retrieve variations of a word (plurals, nouns, etc.) in a database.
The symbol commonly used is the asterisk *.
For example, develop* will retrieve develop, development, developmental, developmentally, developments, etc.
Use truncation carefully.
For example, cat* will retrieve catalogue, catastrophic, catatonic, catfish, catholic …​
You can use a truncation symbol in conjunction with phrase searching. 
For example,  "tandem repeat*" will give the same results for ("tandem repeat" OR "tandem repeats" OR "tandem repeating")

A wildcard replaces a single letter within your word.
For example, behavio?r will retrieve behaviour and behavior; organi?ation will retrieve: organisation and organization
A wildcard can also be used where alternate spelling may contain an extra character, p?ediatric, will search paediatric or pediatric

Wildcard and truncation symbols vary from database to database.
Check the database help section to identify the correct wildcard and truncation symbols.

Contextual limits

Check whether any search limits apply:

  • Animal / Species / Human
  • Age
  • Gender
  • Year(s) of publication
  • Location / Jurisdiction
  • Language(s)

These limits should also be included in your search words, or by using search filters on the database search pages.

Other considerations:

  • most cited authors
  • most relevant journals
  • document types

Database Thesaurus and MeSH (Medical Subject Headings)

See the tab for Using Thesaurus Terms and Subject Headings in Searches

Bring it all together

You can combine all of the elements (keywords, subject headings and synonyms) described above to create a search strategy:

Other database features

Many databases offer a variety of search features including limiting options, thesaurus buttons and field searching, which can enhance your search results.
To find out what specific features a database offers, refer to its search help or tips.

Advanced Database Searching

The Advanced Searching video [5:41mins] describes the process for creating search strings using Boolean operators.

Ask a Librarian to Review Your Search

If your literature search is not resulting in relevant results, you can ask a Librarian to review your search words and search strings by submitting a Murdoch Support request.

Include your topic, initial search words, synonyms, search strings and databases searched.

Subject headings are a set of predetermined terms that describe specific concepts.
Subject headings are also called controlled vocabularies, index terms, or a thesaurus. 

Databases (especially in health) include a thesaurus or subject headings - but not every database utilises subject headings.
Databases may have their own subject headings that do not translate to other databases. 

In addition to identifying search words and synonyms, search the thesaurus or subject headings list to identify relevant terms in the thesaurus, as these are comprehensive.

Examples of database subject headings:

Database name Subject headings
CINAHL CINAHL Subject Headings
MEDLINE (via PubMed or Ovid), Cochrane

Medical Subject Headings (MeSH)

MEDLINE / PubMed Medical Subject Headings (MeSH) : tutorial


APA Thesaurus

PsycINFO thesaurus : tutorial and video

Advantages of using subject headings:

  • controlled vocabulary
  • consistently applied – all articles with the same subject heading will have that as a key concept​
  • assigned by an indexer/librarian after reading the content of the article​
  • compiled into a thesaurus that can be searched.

Combining subject headings with free-text terms will make your search more comprehensive.

To identify subject headings for your search concepts:

  • search the subject heading thesaurus of the database to identify relevant terms for each search concept
  • choose the most relevant term 
  • copy and paste terms into your search planner or other documentation
  • add to both concepts a subject heading that combines the two concepts
  • combine two separate subject headings if required to appropriately describe a concept
  • look at the subject headings used for relevant articles on your topic - do you want to use these as well?
  • add your chosen subject headings as free-text terms (keywords).

The Systematic Searches series of videos from Yale University on systematic searches demonstrate how to build effective search strategies in databases.

Sample Search Strategy

Topic: Toxicological profiling by hair analysis: Detecting and measuring the abuse of illicit drugs​

Concepts and Synonyms:

Concept "hair analysis" detect / measure "illicit drug*​"
Synonyms "hair analy*"






"drugs of abuse"

"illicit drug*​"

"illicit substance*"

"substance abuse"

specific ​drugs such as fentanyl or oxycodone

​Concept strings: 

"hair analy*"

(concentrat* OR detect* OR measure* OR screen* OR test*)

("drugs of abuse" OR "illicit drug*" OR "illicit substance" OR "illicit substance*" OR ​"substance abuse")

Search strategy: ​

  1. ​"hair analy*"
  2. AND (concentrat* OR detect* OR measure* OR screen* OR test*)
  3. AND ("drugs of abuse" OR "illicit drug*" OR "illicit substance*" OR ​"substance abuse" OR fentanyl OR oxycodone)

​Search string: 

"hair analy*" AND (concentrat* OR detect* OR measure* OR screen* OR test*) AND ("drug* of abuse" OR "illicit drug*" OR "illicit substance*" OR "substance abuse" OR fentanyl OR oxycodone)

Sample Search Strategy

Topic: Modelling of water distribution in buildings

Concepts and Synonyms:

Concept modelling "water distribution" building



"water demand"

"water distribution"

"water flow"

"water supply"




​Concept strings: 

(model* OR simulat*)

("water demand" OR "water distribution" OR "water flow" OR "water supply")

(architect* OR build* OR engineer*)

Search strategy: ​

  1. ​(model* OR simulat*)
  2. AND ("water demand" OR "water distribution" OR "water flow" OR "water supply")
  3. AND (architect* OR build* OR engineer*)

​Search string: 

(model* OR simulat*) AND ("water demand" OR "water distribution" OR "water flow" OR "water supply") AND (architect* OR build* OR engineer*)

Sample Search Strategy

Topic: Pathogenesis of Sunshine Virus in Australian snakes

Concepts and Synonyms:

Concept pathogenesis "sunshine virus" snake* Australia








​Concept strings: 

(pathogenesis OR aetiology OR etiology)

("sunshine virus" OR paramyxovirus)

(snake* OR python* OR reptil*)


Search strategy: ​

  1. (pathogenesis OR aetiology OR etiology)
  2. AND ("sunshine virus" OR paramyxovirus)
  3. AND (snake* OR python* OR reptil*)
  4. AND Australia

​Search string: 

(pathogenesis OR aetiology OR etiology) AND ("sunshine virus" OR paramyxovirus) AND (snake* OR python* OR reptil*) AND Australia

Sample Search Strategy

Topic: The association between social media use and adolescent eating disorders

Concepts and Synonyms:

Concept "social media" adolescent eating disorder

"social network*"






"young adult*"




disordered eating


Subject Headings Social Media



Binge-Eating Disorder

Feeding and Eating Disorders

​Concept strings: 

("social media" OR "social network*" OR Facebook OR Instagram OR TikTok)

(adolescen* OR juvenile* OR teen* OR "young adult*" OR youth*)

(anore* OR bulimi* OR "disordered eating" OR "eating disorder*")

Search strategy: ​

  1. ("social media" OR "social network*" OR Facebook OR Instagram OR TikTok)
  2. AND (adolescen* OR juvenile" OR teen* OR "young adult*" OR youth*)
  3. AND (anore* OR bulimi* OR "disordered eating" OR "eating disorder*")

(("social media" OR "social network*" OR Facebook OR Instagram OR TikTok) AND (adolescen* OR juvenile* OR teen* OR "young adult*" OR youth)) AND (anore* OR bulimi* OR "disordered eating" OR "eating disorder*")

PsycINFO search string including subject headings:

((("social media" OR "social network*" OR Facebook OR Instagram OR TikTok) AND (adolescen* OR juvenile* OR teen* OR "young adult*" OR youth*)) AND (anore* OR bulimi* OR "disordered eating" OR "eating disorder*")) AND mainsubject.Exact("adolescent" OR "eating disorders" OR "social media" OR "teen-ager")

PubMed search including MeSH terms:  [PubMed Advanced Search Video]

Search Actions
#8 Search: #1 OR #7
#7 Search: #2 AND #3 AND #6
#6 Search: #4 OR #5
#5 Search: Binge-Eating Disorder[MeSH Terms]
#4 Search: Feeding and Eating Disorders[MeSH Terms]
#3 Search: Teenagers[MeSH Terms]
#2 Search: Social Media[MeSH Terms]
#1 Search: (("social media" OR "social network*" OR Facebook OR Instagram OR TikTok) AND (adolescen* OR juvenile* OR teen* OR "young adult*" OR youth)) AND (anore* OR bulimi* OR "disordered eating" OR "eating disorder*")

Practice Creating a Search String

Identify search words

Pare back the words and add the truncation/stemming Boolean operator  *   e.g. develop*

Ask a Librarian to Review Your Search

If your literature search is not resulting in relevant results, you can ask a Librarian to review your search words and search strings by submitting a Murdoch Support request.

Include your topic, initial search words, synonyms, search strings and databases searched.

Locating the Literature

Search tools:


Databases are the major resource for finding journal articles and have important functionality.​ ​

If you learn how to use databases effectively, your research will be much more productive and of much higher quality​ ​

Databases may be multidisciplinary or subject specific​ ​.

Databases help you use keywords to find a list of relevant resources on a topic.

The databases subscribed to by the the Murdoch University Library  are produced by scholarly publishers, with all content peer-reviewed.
They are collections of citations (or references) to journal articles, conference papers, books, etc.
They may include citations; citations and abstracts; or citations, abstracts and full text articles.

Databases have different searching interfaces - with different terminology and techniques for searching, so for information about how best to search a database, use the Help option within that database.

For a comprehensive literature search, you will need to use more than one database

Subject guides include lists of relevant databases:

The list of All Databases can be searched by database title or by subject to see the key databases in your area of research.  

Database Alerting Services

Many databases including Scopus, Web of Science, Medline, PsycINFO, and others allow you to save searches and create alerts​ ​

You may be required to create a personal login, this is free and easy - always use your Murdoch email address for this purpose​ ​

You will be emailed when new references relevant to your search are published and added to the database​ ​

Alerts can be individually scheduled

Mine Reference Lists / Citations

Identify the most cited relevant references from the reference list in articles.

You can then search for the most cited articles, to see other relevant articles that have also cited these articles.

This is useful if you have a scope of, for example, the last 5 years, and find a seminal article outside this date scope.

Search for the seminal article, using the filter of past 5 years, to source articles citing the seminal article that have recently cited this work.

Library Search

Library Search is the easiest way to search the Library’s print and digital resources from a single search box. It's a quick way to locate items you may already have details about or a useful tool when you need to find high quality resources on a topic.

However, you should use databases rather than Library Search when you need to find comprehensive or specialised information in your subject area.

Search results can be refined by filters such as Publication Date, Peer-Reviewed, Content Type, or Subject.

The How to use Library Search page has more detailed information.


Resource Sharing

If a particular book, journal article or other resource is not held in the University Library, you can request it from another library using our free services:

  • Document Delivery - allows you to request material from other libraries
  • In person - borrow books from other university libraries in Western Australia
Google Scholar

Google Scholar is not a substitute for databases, but can be useful.

Set up Google Scholar to source articles from the Murdoch University Library's resources.

Go to Google Scholar.

Click on the 3 lines in the top left of screen (hamburger menu icon).

Select Settings.

Select Library links from the Settings menu. 

Type 'Murdoch' into the search box and click Find Library.

Tick the box next to  .

Save your new settings.

Now when you search for articles in Google Scholar, you will see a link to Murdoch to the right in the Results list if the articles are in our collection.

This will make it easier for you to determine the title of the journal the articles or studies are published in.

You can then search Ulrichsweb to check if the article is from a peer-review journal.

Scroll down page


Document Your Search

Your search process must be documented in enough detail to ensure that it can be reported correctly.

For each database search you conduct, you should record:

  • The date the search was run
  • The database searched
  • The name of the database provider (for example: ProQuest or EBSCO)
  • Your search strategy - include the keywords you used and how these were combined in the search
  • The years searched
  • Any filters or limitations used, such as date, language, age or demographics
  • The number of studies identified

It may be useful to save your search strategies in the databases you use (where possible) to refer back to later.
Resources such as Medline, Scopus, Web of Science and Cochrane provide this feature.

EndNote software can also be used to record full bibliographical details for each citation and additional notes relating to the selection and evaluation of that source.

Searching the Literature Checklist

  1. Have you discussed relevant resources with your supervisor?
  2. Have you considered keeping a search diary?
  3. Have you developed a potential search strategy before starting to search?
  4. Have you fully described the keywords and concepts for your review topic and the relationship between these keywords and concepts?
  5. Have you identified the most appropriate databases and other resources for your literature search?
  6. Do you know how to locate any resources that are not held by the University Library?
  7. Have you sought assistance from our Librarians?

Grey literature

The term grey literature "is usually understood to mean literature that is not formally published in sources such as books or journal articles" (Lefebvre, Manheimer, & Glanville, 2008, p. 106).

Grey literature may include multiple types of document produced on all levels of government and by academics, businesses and organisations  in electronic and print formats where publishing is not the primary activity of the producing body. (Greynet, 2015.)    

Examples are:

  • clinical trials
  • conference proceedings
  • economic data
  • ephemera
  • geospatial data
  • infographics
  • interviews
  • maps
  • meeting notes or minutes
  • newsletters, emails, blogs and other social networking sites (examples of community based grey literature)
  • official documents
  • patents
  • personal memoirs
  • policy statements
  • posters
  • practice guidelines
  • reports (reports of government and research institutes are generally freely available on the internet)
  • standards
  • technical specifications and standards
  • technical and commercial documentation
  • theses
  • translations

There may also be grey literature that is specifically relevant to your discipline.
Practice guidelines are highly relevant to nursing and health professions, working papers are used in the social sciences (particularly economics) and patents are important to engineering.

A systematic review conducted in 2008 by members of the Cochrane methodologies team found that  the results from grey literature often have a significant effect on the outcome of a review, as they often report more negative or inconclusive data than published journal articles (Hopewell et al., 2008). 
As such, it is important to treat grey literature as another potential source of studies for inclusion while noting that it is usually not subject to peer review and must be evaluated accordingly.


1. Alberani, V., De Castro Pietrangeli, P. & Mazza, A.M.  (1990).  The use of grey literature in health sciences: A preliminary survey.  Bulletin of the Medical Library Association, 78 (4) : 358-363. Retrieved from 
2. GreyNet International (2015). Retrieved from
3. Lefebvre C, Manheimer E, Glanville J. (2008). Searching for studies. In: J.P.T. Higgins & S. Green (Eds.), Cochrane handbook for systematic reviews of interventions. Chichester: Wiley-Blackwell.
4. Hopewell S, McDonald S, Clarke M, & Egger M. (2007).
Grey literature in meta-analyses of randomized trials of health care interventions. The Cochrane Library.  doi: 10.1002/14651858.MR000010.pub3


The first step in evidence-based practice is to define your clinical question. There are many frameworks that you can use in formulating your question, such as PICO. Find out more about clinical questions on the following pages:


Once you have a well-formulated clinical question, you can start searching the literature. Refer to the 'Journals and Databases' page for databases related to your topic.

You should also look at the following of databases with evidence based materials:

Database Description

Joanna Briggs Institute

Resources for evidence-based research including best practice information sheets, systematic reviews and electronic journals and conference papers. Consumer health-care information is also available. Some content is only accessible via login and password through the Members Area.

Cochrane Library 

The Cochrane Library comprises several databases of reviews of the effects of health care. Included is the Cochrane Database of Systematic Reviews - evidence-based systematic reviews prepared by the Cochrane Collaboration to provide high quality information to people providing and receiving care and those responsible for research, teaching, funding and administration at all levels.


Once you have located some relevant literature, you will need to critically appraise the evidence.

There are many different types of study designs, which would affect how you would appraise the individual studies, and thus the weight you give each study. This is commonly represented in what is know as the Level of Evidence hierarchy.

Hierarchy of evidence pyramid. (Aslam, Georgiev, Mehta & Kumar, 2012)  CC BY-NC-SA 3.0

Some key resource for appraising literature are:

For more information and tools on critical appraisal of the literature, please go to:


Aslam, S., Georgiev, H., Mehta, K., & Kumar, A. (2012). Matching research design to clinical research questions. Indian Journal of Sexually Transmitted Diseases and AIDS, 33, 49-53. Retrieved from:


The key elements of evidence-based practice are:

  • Best research evidence
  • Clinical expertise
  • Patient values and circumstances.

Elements of EBP Creative Commons License

When applying the studies you have found in practice, it is important to do so in the context of the other two elements.


Once you have implemented your evidence-based practice, you need to audit and evaluate it to see if it is effective.

Please refer to Chapter 8 of Evidence-based medicine: How to practice and teach EBM by Straus, Glasziou, Richardson and Haynes for guidance on how to do this.


Australian Government Information

Government departments (State and Commonwealth) can be found using Google. Some useful sites are listed below:

International Sources


University repositories, such as the Murdoch Research Portal, can be used to locate theses, research papers and data if they have been made available.
Information about locating theses and dissertations can be found in the Murdoch Library Theses Guide.


Databases That Include Grey Literature

Use the Document Type/Source Type/ Publication Type filters to search for specific formats of grey literature.

In addition to the sources listed above, internet searching can locate other useful sources:

  • Remember there are two spellings and search for (gray OR grey) literature when searching for grey literature in general
  • Find and search the online catalogues of large libraries
  • Search for the host sites of conferences and academic associations for conference papers or proceedings
  • To find conference papers in Web of Science, enter your search terms, and on the results page see 'Document Types' in the 'Refine your results' panel and select 'Proceeding Paper'
  • Try restricting your search to the .org and/or .gov domains
Grey literature search words

When developing a search strategy, specify what type of content is to appear in search results.

Example search words to include:


thesis OR dissertation OR doctorate

government AND (report OR strategy)

"working paper" OR "white paper" OR "green paper"​

(conference OR seminar OR symposium OR workshop) AND (paper OR proceedings)

Internet searches can include file types:

ofiletype:xls OR xlsx

You should evaluate grey literature in the same way as other document types that are included in your research.

  • Currency - does the date fit with the research purpose? It is best to leave the data if a date cannot be found.
  • Relevance - is it significant? Does it enrich or have an impact on the research? Have limitations been imposed and are these stated clearly?
  • Authority - has the report come from a reputable institution or organisation?
  • Accuracy -  is it supported by documented and authoritative references? Is there a clearly stated methodology?
  • Bias - is the source objective? Look carefully at commercial or political sources for funding bias. Studies with more 'positive' results - those which show a definite effect for an intervention - are three times more likely to be published than ones which show little or no positive effect.

The AACODS checklist created by Flinders University is also a useful tool for evaluation and critical appraisal of grey literature.